Do I want soft solder or hard solder?Solder comes in soft, medium, hard and now extra easy. This simply indicates the difference in temperature required to get the solder to flow. Soft flows at a lower temperature than medium and so on. This is important if you are going to be soldering multiple layers of metal on the same piece. You would solder with a harder (higher temp) solder the first time and a comparatively softer (lower temp) solder the second time. This will keep previous joints from re-flowing. If you only need to solder one time, you can use any level but you might as well use soft or medium to save time and fuel.